Generally, an Electronic Service Guide (ESG) enables a terminal to communicate what services are available to end users and how the services may be accessed. ESG fragments are independently existing pieces of the ESG. Traditionally, ESG fragments comprise XML documents or fragments of XML documents, but more recently they have encompassed a vast array of items, such as for example, a SDP (Session Description Protocol) description, textual file, or an image. The ESG fragments describe one or several aspects of currently available (or future) services or broadcast programs. Such aspects may include for example: free text description, schedule, geographical availability, price, purchase method, genre, and supplementary information such as preview images or clips. Audio, video and other types of data comprising the ESG fragments may be transmitted through a variety of types of networks according to many different protocols. For example, data can be transmitted through a collection of networks usually referred to as the “Internet” using protocols of the Internet protocol suite, such as Internet Protocol (IP) and User Datagram Protocol (UDP). ESG fragments may also be transmitted using ALC and FLUTE protocols. Data is often transmitted through the Internet addressed to a single user. It can, however, be addressed to a group of users, commonly known as multicasting. In the case in which the data is addressed to all users it is called broadcasting.
One way of broadcasting data is to use an IP data casting (IPDC) network. IPDC is a combination of digital broadband broadcast and Internet Protocol. Through such an IP-based broadcasting network, one or more service providers can supply different types of IP services including on-line newspapers, radio, and television. These IP services are organized into one or more media streams in the form of audio, video and/or other types of data. To determine when and where these streams occur, users refer to an electronic service guide (ESG). One example used in digital video broadcasting (DVB) streams is an electronic program guide (EPG). One type of DVB is Digital Video Broadcasting-Handheld (DVB-H), a technology that increases the capabilities and services available on small handheld devices, such as mobile telephones. The DVB-H is designed to deliver data to a battery-powered terminal device.
Mobile battery-powered terminal devices come in many shapes and sizes, with differing software, differing user interfaces, and differing hardware capabilities. For example, some mobile terminal devices may have different types of hardware and/or software radios than other mobile terminal devices, e.g., WLAN transceivers, FM radio receivers, DVB-H receivers, telecommunications transceivers, etc. Other devices may include different software applications than other devices, and use different user interfaces. The variety of hardware and software configurations makes it difficult to efficiently and uniformly implement DVB and other broadcast and/or multicast services on a mobile terminal device.